127 lines
4.9 KiB
ArmAsm
127 lines
4.9 KiB
ArmAsm
/*
|
|
Copyright Oliver Kowalke 2009.
|
|
Distributed under the Boost Software License, Version 1.0.
|
|
(See accompanying file LICENSE_1_0.txt or copy at
|
|
http://www.boost.org/LICENSE_1_0.txt)
|
|
*/
|
|
|
|
/*******************************************************
|
|
* *
|
|
* ------------------------------------------------- *
|
|
* | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | *
|
|
* ------------------------------------------------- *
|
|
* | 0 | 4 | 8 | 12 | 16 | 20 | 24 | 28 | *
|
|
* ------------------------------------------------- *
|
|
* | TOC | R14 | R15 | R16 | *
|
|
* ------------------------------------------------- *
|
|
* ------------------------------------------------- *
|
|
* | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | *
|
|
* ------------------------------------------------- *
|
|
* | 32 | 36 | 40 | 44 | 48 | 52 | 56 | 60 | *
|
|
* ------------------------------------------------- *
|
|
* | R17 | R18 | R19 | R20 | *
|
|
* ------------------------------------------------- *
|
|
* ------------------------------------------------- *
|
|
* | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | *
|
|
* ------------------------------------------------- *
|
|
* | 64 | 68 | 72 | 76 | 80 | 84 | 88 | 92 | *
|
|
* ------------------------------------------------- *
|
|
* | R21 | R22 | R23 | R24 | *
|
|
* ------------------------------------------------- *
|
|
* ------------------------------------------------- *
|
|
* | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | *
|
|
* ------------------------------------------------- *
|
|
* | 96 | 100 | 104 | 108 | 112 | 116 | 120 | 124 | *
|
|
* ------------------------------------------------- *
|
|
* | R25 | R26 | R27 | R28 | *
|
|
* ------------------------------------------------- *
|
|
* ------------------------------------------------- *
|
|
* | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | *
|
|
* ------------------------------------------------- *
|
|
* | 128 | 132 | 136 | 140 | 144 | 148 | 152 | 156 | *
|
|
* ------------------------------------------------- *
|
|
* | R29 | R30 | R31 | hidden | *
|
|
* ------------------------------------------------- *
|
|
* ------------------------------------------------- *
|
|
* | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | *
|
|
* ------------------------------------------------- *
|
|
* | 160 | 164 | 168 | 172 | 176 | 180 | 184 | 188 | *
|
|
* ------------------------------------------------- *
|
|
* | CR | LR | PC | back-chain| *
|
|
* ------------------------------------------------- *
|
|
* ------------------------------------------------- *
|
|
* | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | *
|
|
* ------------------------------------------------- *
|
|
* | 192 | 196 | 200 | 204 | 208 | 212 | 216 | 220 | *
|
|
* ------------------------------------------------- *
|
|
* | cr saved | lr saved | compiler | linker | *
|
|
* ------------------------------------------------- *
|
|
* ------------------------------------------------- *
|
|
* | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | *
|
|
* ------------------------------------------------- *
|
|
* | 224 | 228 | 232 | 236 | 240 | 244 | 248 | 252 | *
|
|
* ------------------------------------------------- *
|
|
* | TOC saved | FCTX | DATA | | *
|
|
* ------------------------------------------------- *
|
|
* *
|
|
|
|
.text
|
|
.globl _ostd_make_fcontext
|
|
_ostd_make_fcontext:
|
|
; save return address into R6
|
|
mflr r6
|
|
|
|
; first arg of ostd_make_fcontext() == top address of context-function
|
|
; shift address in R3 to lower 16 byte boundary
|
|
clrrwi r3, r3, 4
|
|
|
|
; reserve space for context-data on context-stack
|
|
; including 64 byte of linkage + parameter area (R1 16 == 0)
|
|
subi r3, r3, 248
|
|
|
|
; third arg of ostd_make_fcontext() == address of context-function
|
|
stw r5, 176(r3)
|
|
|
|
; set back-chain to zero
|
|
li %r0, 0
|
|
std %r0, 184(%r3)
|
|
|
|
; compute address of returned transfer_t
|
|
addi %r0, %r3, 232
|
|
mr %r4, %r0
|
|
std %r4, 152(%r3)
|
|
|
|
; load LR
|
|
mflr r0
|
|
; jump to label 1
|
|
bl l1
|
|
l1:
|
|
; load LR into R4
|
|
mflr r4
|
|
; compute abs address of label finish
|
|
addi r4, r4, lo16((finish - .) + 4)
|
|
; restore LR
|
|
mtlr r0
|
|
; save address of finish as return-address for context-function
|
|
; will be entered after context-function returns
|
|
std r4, 168(r3)
|
|
|
|
; restore return address from R6
|
|
mtlr r6
|
|
|
|
blr ; return pointer to context-data
|
|
|
|
finish:
|
|
; save return address into R0
|
|
mflr r0
|
|
; save return address on stack, set up stack frame
|
|
stw r0, 8(r1)
|
|
; allocate stack space, R1 16 == 0
|
|
stwu r1, -32(r1)
|
|
|
|
; set return value to zero
|
|
li r3, 0
|
|
; exit application
|
|
bl __exit
|
|
nop
|